no edit summary
Line 62: Line 62:  
* For parturition to occur, progesterone production by the Corpus Luteum must be terminated.
 
* For parturition to occur, progesterone production by the Corpus Luteum must be terminated.
 
* As the foetus grows in a restrictive environment it becomes stressed.  Stress leades to a rise in foetal [[Endocrine_System_-_Pituitary_Gland_-_Anatomy_%26_Physiology#Hormones_of_the_Anterior_Pituitary_Gland|ACTH]].  The rise in ACTH causes production of Cortisol from the foetal [[Endocrine_System_-_Adrenal_Glands_-_Anatomy_%26_Physiology|Adrenal Glands]].
 
* As the foetus grows in a restrictive environment it becomes stressed.  Stress leades to a rise in foetal [[Endocrine_System_-_Pituitary_Gland_-_Anatomy_%26_Physiology#Hormones_of_the_Anterior_Pituitary_Gland|ACTH]].  The rise in ACTH causes production of Cortisol from the foetal [[Endocrine_System_-_Adrenal_Glands_-_Anatomy_%26_Physiology|Adrenal Glands]].
 +
* The rise in foetal cortisol leased to an increased Oestrogen:Progesterone ratio by upregulating '''Aromatase''' enzymes which convert Androgens to Oestrogens.  Cortisol also reduces Progesterone production.
 +
 +
 +
''Species that depend on Placental Progesterone in late pregnancy (Ewe,Guinea Pig,Queen,Mare)''
4,503

edits